Fabricated-steel derrick or tower construction



July l0, 1928.

' C. B. FOSTER FABRICATED STEEL DERRTCK 0R TOWER CONSTRUCTION 3Sheets-Sheet Filed July 1.7, 1926 July 10, 1928.

c. B. FOSTER"v FABRICATED STEEL DERRICK OR TOWER CONSTRUCTION` FiledJuly 1'?. 192e s Smets-sheet 2 i if( y INVENTOR.

I B. FOSTER FABRICATED STEEL DERRICK OR TO WER CONSTRUCTION 3Sheets-Sheet 5 Filed July 17, 1926 NVENTOR.

July l0, 1928.

Patented July 10, 1928.v

- UNITED stares 1,676,539 sp ATE Nr 'io-Fries.

CLARENCE B. FOSTER, oF. eLENnALE,A cALIroRNIA, AssIGNoR 0E ONE-SIXTH-TO'IRED- ERICR L. FEISTIIAMEL, oNE-sIXTII To ARTHUR J. CARR, 4AND`oNE-sIXfrH 'roV THOMAS A. COLLINS, ALL 0F Los ANGELES, CALIFORNIA.

FABRICATED-STE'EL DERRICK vOR TOWER CONSTRUCTION.

Application 1ed`Ju1y17,1926. Serial No. 123,135.

This invention relates to an improved vtype lof Afabricated steelderrick ortower construction, and is particularly Vdirected to thatclass of -structure'in Awhich vthe corner leg columns and .associated'girts are formed of `standard structural angles.' Y l Morespecifically, the present invention yis directed to certa-inimprovements in the construction of the type of derrick or towerdisclosed in ymy copending application, Serial No. 123,134, and vhas foran objject'to V,provide a structure including a triple-angle type ofcorner leg column in rwhich the three angle leg sections thereof arearranged in back-tobickrelationship Ito form a leg column crossshaped incross section, and with `the y leg angles secured together in intimatecontacting relationship throughout their lengths.V

Another object is to provide. an improved form of compound gussetbracket associated with the corner leg column `and thegirts and bracesof the adjacent. sides ofthe structure `to form reinforcing means freefrom connrction to the outer intermediate leg angle, said bracketconstituting a means providing directl connection between the girts andbraces of the adjacent sides.

' A further object is to provide a compound.

horizontal and; vertical gusset bracketwhich may be formed of-a singlevsheet metal stamping bent to form a horizontalgussetofdoubleAthickn-css,and two vertical gussets langularly disposed to each other.f I

Various other objects and advantages will be more fully .apparent fromthe following description of the accompanying drawings which form a partof this disclosurepand which illustrate a preferred Fform of embodimentofthe invention.

Oftlie drawings; Fig. l. is an elevation of a 'tower structureconstructed in `accordance with thel present invention.

Fig. 2 is an enlarged plan section, lpartly broken, taken. on line 2-2ofFig. l.

Fig. 3 is a fragi'nentary vertical section taken'on lineBMSof Fig. 2.

Fig. Yl is a fragmentary elevation of a corner :portion ofthe tower,looking outwardly in Ythe .direction indicated by the arrow 4e inFig. 2.i v

Fig. 5 is a'pl'an view of the-gusset bracket Vblank before Abeing bentto form.

invention.

Fig. 6 is a perspective view of one of the .gusset lbracketsas it will.appear before the boltholes. are punched therein.

Fig. 7 is an elevationofa drilling derrick constructed in accordanceFig. 8 is an enlarged Afragmentary elevation :of one corner ofthederrick as it will appear with the .present with theouter-.intermediate leg angles lre- 1 moved. p

Fig. 9 isa similar .elevation .showing the angle joint-.plates which maybeused to replace the removed intermediate vleg angles. In theconstruction disclosed in my other application, above identified, thecorner leg column consisted of two opposed linner leg angles and anouterintermediate leg angle spaced from saidinnerleg angles to accommodatethe anchorplates of the respective compound gusset brackets and veach ofsaid brackets provided a horizontal gusset of single thickness.r y i.For certain purposes it has been found de# sirable to provide a triplevangle Fleg column I in which the several angle leg ksections .areclamped together in lintimate contacting relationship throughout theirrespective lengths so as Ito .produce `a more "rigid corner column inwhichshear strainsv on the bolts or rivets of the ,-leg 'angles 4isminimized .by

the `resistance yagainst relative slippage of the respective .leg anglesdue to the intimate clamped contact -of the 'leg angles, itbeingrecognized that such boltsor rivetscannotbe subjected to shear untilslippage 4occurs .and

that the resistance to slippage of clamped surfaces rhas an acceptedvalue fof `approximately l8',000 pounds'per square inch, which willsubstantially equal Ithe Ashear strengthVV of the bolts or :rivets used.

It vwill Ithus fbe quite evident that 'the importance of closelycontacting and tightly clamping together the leg angles comprising thecorner .-legs assumes a major aspect of thisinvention The formA ofgusset bracketincorporated -in `the structure herein disclosed-is-oflparticular value byfreason'of the-horizontal gussets of doublethickness -`thereby provided" and for the reason that fthe vertical'Kgussets are joined to each other throughout ltheir height, a furtheradvantage being that the bracket is fully independento'f any .connectionwith the' .outer intermediate .leg .angle which is intended for removalfor the conversion of the structure from a heavy duty type to oneadaptable for lighter' service.

v In Figs. 1 to 6 there is illustrated a heavy duty type of structure inthe form of a square tower having'four corner leg columns connectedtogether by transverse girts and diagonal sway braces which form `there,- spective sides of the structure. The several corner leg columns areof duplicate construction and each is formed of three strings of anglesections disposed in back-to-back relationship to form a leg columnsubstantially cross-shape in cross section, with the sections of eachstring vertically aligned to abut one upon the other.

The inner' opposed angle leg sections 10 and 11 are ldisposedzwith theirrespective flanges 1021 and 11a extended in the planes of the respectiveadjacent sides of the towel' and with their other flanges 10b and 11bextending outwardly, and the respective leg sections 10 and 11 of theseveral corner leg columns are arranged in horizontal alignment so as tobring the several lines 12 of abutment at coincident vertically spacedintervals, whereby the tower may be assembled progresively in stories ortiers to a horizontal level. vThe outer intermediate angle leg sections13 are disposed between the inner opposed leg sections'l() and 11 withtheir flanges in direct intimate contact with the flanges 10b and 11b ofsaid inner' leg angles and said outer leg Vanglesv are disposed inbreak-joint relationship with the inner leg angles'lO and 11 so thattheir ylines 14 of abutment come half way between those ofv the innerleg angles, as shown in Fig 1.

Disposed at each end of each pair of inner leg angles sections 10' and11 is a compound gusset bracket of'novel construction, formed to providetwo vertical Vgusset plates 15 and 16 disposed at right angles to eachother and joined at their inner vertical edges, and two vhorizontalgusset plates 17 and 17a extended from the respective vertical gussetplates 15 and 16 and disposed in overlapping` relationship ytoconstitute a horizontal gusset of "double thickness. This' gussetbracketis preferably formed of a single Y' sheet metal stamping of thecontour illusf stamping,

trated in Fig. 5, said stamping being formed with a central aperture20vand a slit 21 extending inwardly to intersect said aperture. In theforming of the bracket from vsaid the vertical gusset portions 15 and 16may be bent towards each other, along lthe line 18, the portion 17 beingthen bent 'at right angles to the portion 15, along the line 15a, andthe portion 17a being subsequently bent, along the lines 16a, toposition parallel and in -overlapping relationship with the portion 17,thus forming a bracket of substantially the shape illustrated in Fig. 6,said bracket being, by preference,

subsequently punched or bored to accommodate the several rivets orvbolts by which it is secured into thetower structure.

At each level or tier of the Vtower structure, as defined by the line 12of abutment between the vertically adjacent innerleg angles, two of theabove described gusset bracket-s are positioned 4in lreverse relationship with their respective horizontal gusset plates 17a back-to-back andtheir respective vertical gusset plates extended in opposite directions;andsuch brackets are disposed so that their vertical gusset plates 15and 16 closely engage the inner surfaces of ythe flanges 10a and 11L ofthe respective inner leg angles 10 and 11, as clearly shown in Fig. 2,these particular gusset brackets being indicated generally, by thereferencevcharacters A and B. Y Y

Certain other intermediate gusset brackets C and D, similar to thoseabove described, are preferably located at approximately the middle ofthe respective pairs of inner leg angles 10 and 11 of each corner columnand are disposed in the same relationship tothe several leg angles asare the gusset-brackets A and B, that is, each pair of gusset brackets Cand D are in reverse relationship vertically with their vertical gussetplates engaging the leg angles 10 and 11 and their horizontal gussets inback-to-back relationship.

In erecting the structure, the several leg 'sections are clampedtogether in contacting relationship, by bolts 22, 23, and 211, the bolts22 extending through the flange 1()b of the lrespective leg angles 1()and the contacting llt) of the respective outer leg angles 18, it beingunderstood that a greater number of the bolts 24 and 28, between thepairs of gusset brackets, may be provided if desired.

The side structure connecting the adjacent corner leg columns isillustrated as comprise ing a plurality of girts and braces, and as suchgirts and braces included in each story or tier are duplicates of thoseincluded in the other stories or tiers, only one set thereof will hereinbe described in detail` The s sides of each story includes lower andupper transverse marginal girts 30 and- 31, so called because theydefine the respective lower and upper margins of the respective story, apair of intermediate transverse girts 32 and 33, a lower pair ofdiagonal sway or anti-vibration braces 34C and 35, and an upperpair of.similar sway or y.anti-vibration braces 36 The'severa'l*transverse girtsare of angle 'form andmaybe-of identical size and shape, With the endsof their horizontal flanges cut angular as shown 'in F ig. 2, and therespective ends of each girt are disposed in'neste-d relationship insidethe cooperating gusset vbracket with the horizontal flange ofsaid v'girtengagingthe horizontal gusset :plate k17 v fbracket, and "issecured tosaid bracket 'and the'a-djacent inner' leg angle by abolt 4l eX-`tending through said vertical 'gusset portion ofthe bracket and throughsaid inner leg anglefsaid vertical .gusset plate 'portion of theVbracket being thus clampedv between -said girt and saiddnner' legangle,'as is plainly evident in Fig. "2. Bolts 42 extending through thehorizontal flanges of 'the respective girts and `through thehorizontalgusset'plates 17l and 17a of each pairv of brackets A, Bya'ndC, D,'thus securing said pairs of brackets together independently oftheir connection with the corner legs, and

said horizontal gusset plates 17 and 17a are Lfurther secured4 togetherindependently also of thegi'rts, by bolts 43.

VThe several diagonalsWay braces are of angle form and their ends areswayed to :bring Vboth flanges 'thereof 'to vertical par- .allellcontact thusproviding securing ends of double thickness. These'respective sway braces are each secured to the .vertical 'gussetplateportions of the associated brackets fby bolts 44 and 45, the 'bolts44extending through saidbr'aces and the V`vertical gusset vplate portion-sof said brackets and the lbolts 45feXtending through said braces, said.brackets and "the adjacent 'inner vangle leg Y sections. f

The above` described 'l construction provides a tower vor similarstructure in which .the respective corner leg columns each con-- sistsof three strings of angle leg' sectionsarranged in back-to-backrelationship and secured together throughout their lengths in `intimatecontact to form corner "legs substantially cross-shapein cross section,Vand ktransverse -girts and braces Yconnected to saidcorner "legs bycompound horizontal and vertical ygusset* Iibr'ackets,1 With v'such.gusset brackets forming reinforcing connec- Vt-ions joining thehorizontal girts and braces of one side of the "tower to vthose of theadjacent sides thereof. Such construction further-provides corner legcolumns consisting of two vertical strings of opposed inner corner -legangles and an -intermediate string of vouter corner leg angles connectedrtogether in a manner permittinga removalof said outer leg angles toconvert the structure to one adaptable dor luse *for lighter service.

.In Fig. 7, the above described construction is shown' incorporated Ain'an oil Well drilling derric'k, and when such a derrick is lto beconverted to a lighter pumping derrick the outerleg angles 13 thereofwill be removed, Figg showing a corner `of the derrick with such legangles removed. fI'n.' lcertain instances the structure may be used .inthis condition, but it is believed to be desirable to substitute lforthe removed-leg angles, short angle yjoint-'plates `50, as-shovvn `inFigy'9, 'these joint-plates being securedL r-in place by bolts 51 `Whichextend through the vsame bolt holes as did the respective bolts 22, 23,26, and 27 previously'fused to secure the leg angles 13 in place. v

The several stories 'or t'iers of the ltower are herein described asbeing of like'construction, but it is tobe understood 'that this v:hasmore particularly reference tothe major lportion thereof, for 'it Willbe evident, particularly to those skilled in the oil :industry that in aWell derrick certain lportions yof lthe structure Will necessarily besomewhat inodied to accommodate the Walking-beam draw-Works, and otherportions'ofthe drilling or pumping equipment andalso 'that suitablelprovisions will 'be made"'for"`the derrick ladder, platform,`Water-table, vcrown-block, etc.

\ While the Vstructure herein'illustrated and described yis fullycapable of `fulfilling all of 'the objects :primarily stated, 'it is tobe understood'that :I do not Wish to restrict the present invention tothe specific 'embodiment herein-disclosed, for it is susceptible ofembodiment in various-other forms, all coming- Within the scope of theclaims, which follow.

I y'claim as my invention:

l. In a structure Vofthe nature disclosed, i

-the combination of: relatively spaced tripleangle corner leg columns,each'comprised-of 'only two opposed inner -leg'angles and -oneintermediate louter leg angle disposed `inintimateback-to-back'contactlto form a compact corner leg `columnsubstantially cross- ,shape in cross section ;transverse girt-s -formingAtheV .respective 4sides rof the structure and connectingthe adjacentcorner :leg columns,

'the'girts ofeach side being secured at opposite-ends'to vthea'djacentinner leg angles of the :associated leg columns; means connect" ing the4innerleg angles of each corner colum'n independently df 'the`intermediate leg :angles 1thereof; andfindependent removable "means forjse'curing vthe intermedi-ate leg 4angle "of each corner/column to th'einner leg angles thereof, whereby the intermediate leg angles may beindependently removed.

2. In a structure ofthe nature disclosed the combination of: relativelyspaced tripleangle corner leg columns, each comprised of only twoopposed innerl leg angles and one intermediateouter leg angle disposedin intimate back-to-back contact to form a com- .pact corner leg columnsubstantially crossshape in cross section, with one flange of each innerleg angle disposed parallel to the adjacent side ofthe structure;transverse girts forming the respective sides of ther structure andconnecting the adjacent corner leg columns, the girts of each side beingsecured t-o the Vrespective parallel flanges of the adjacent inner legangles; means connecting said flanges of both inner leg angles ofv eachcorner leg column inde-v pendently of the intermediate leg anglethereof; and removable means for securing the other flanges of bothinnerleg angles of each corner legI column to the intermediate leg anglethereof, whereby said intermediate leg angle may be` independentlyremoved. z y

3. In a structure of the nature disclosed, the combina-tion of:relatively spaced tripleangle corner leg columns. each comprised of onlytwo opposed inner leg angles and one intermediate outer leg angledisposed in intiv mate back-to-back contact to form a compact corner legcolumn substantially cross-shape in cross section; transverse girtsforming the respective sides of the structure and connecting theadjacent corner leg columns;

.means for securing the girts of eac-h side to the adjacent inner legangle ofeach associated corner column; and independent removable meansfor securing the intermediate leg angle only to the inner. leg angles,whereby said intermediate leg angle may be sepaf rately removed.

4t. In a structure ofthe nature disclosed, the combina-tion of:relatively spaced tripleangle corner leg columnseach comprised of onlytwo opposed strings of inner leg angles and one intermediate string ofouter leg angles arranged in intimate back-to-back contact to form acompact corner leg column substantially cross-shape in cross section,the leg angles of each string being vertically aligned to abut one uponanother, the inner angles only to the inner leg angles, whereby saidintermediate leg angles'may be rately removed.

In a structure of the nature disclosed, the combination of: relativelyspaced tripleangle corner leg columns, eachl comprised of two opposedstrings of inner leg angles and an intermediate string of outer legangles arranged in intimate back-to-back contact to form a compactcorner leg column substantially cross-shape vin cross section, the legangles of each string beingvvertically aligned to abut -one uponanother, the inner leg angles of said two opposed strings beinghorizontally aligned so that the leg angles of both-said opposedstringsabut at'coinc-ident' pendentlyv of the intermediate leg anglessepathereof; and independent means for securing the intermediate legangles only to the inner leg angles, whereby said intermediate legangles may be separately removed.

6. In a structure of the nature disclosed, the combination of:relatively spaced corner leg columns each formed of two opposed stringsof vertically aligned leg angles with the'flanges of each stringdisposed at right angles to the-adjacent flanges of the .opposed string,and with the inner flange of each string disposed parallel to theadjacent side of the structure and the other flange thereof extendedoutwardly, the leg angles of both strings being horizontally aligned tobring their respective abutment joints at coincident levels; transversegirts forming the respective sides of the structure and connecting theadjacent leg columns; means for securing the girts of each side to theadjacent inner flanges of theV associated leg columns; intermediateangle connecting elements associated with each corner leg column anddisposed between and in intimate contact with the outer anges of bothstrings of leg angles thereof in positions to span said respectiveabutment joints; and separate means for securing said connectingelementsto said outer flanges of the leg angles of both opposed strings.. j

7. A compound gusset bracket for a fabricated steel structure,comprised, of: two angularly disposed yvertical gusset plate portionshaving their adjacent vertical edges joined together; and two horizontalgusset plate portions each connected to ahorizontal edge of one of saidvertical gusset plate portions, said horizontal gussetl plate portionsextending inwardly in overlapping relation- Aprovide a two-plyhorizontal gusset.

9. In a structure of the nature disclosed, the combination of:relatively spaced tripleangle corner leg columns, each comprised of.only two opposed strings of vertically aligned leg angles and oneintermediate vstring of vertically aligned leg angles arranged inintimate back-to-back contact to form a compact corner leg columnsubstantially cross-shape in cross section, the leg angles of bothopposed strings of all of said leg columns being respectively ofcorresponding lengths so as to break joint at coincident levels, and theintermediate leg angles of each corner column being disposed inbreak-joint relationship with those of the companion opposed strings;and transverse girts forming the respective sides of the structure andconnecting the adjacent corner leg columns, the girts of each side beingsecured to the adjacent opposed stringsof the` associated corner legcolumns independently of the intermediate leg angles thereof.

10. In a structure of the nature disclosed, the combination of: atriple-angle corner leg column formed of two opposed strings ofvertically aligned inner leg angles with the angles of each stringhorizontally aligned with those of the other string and an intermediatestring of vertically aligned outer leg angles disposed in break-jointrelationship with said inner leg angles, the three strings of leg anglesbeing arranged in intimate back-to-back contact to form a compact cornerleg column substantially crossshape in cross section; reinforcingbrackets positioned at opposite ends' of said inner leg angles andsecured thereto to form direct connections between both strings of innerlegangles; transverse girts forming adjacent sides of the structure, thegirts of each side being secured Ato the adjacent inner leg securing theintermediate leg angles only to the inner leg angles, whereby saidintermediate leg angles may be separately removed.

l1. In a structure ofthe nature disclosed, the combination of: atriple-angle corner leg lcolumn formed of two inner strings ofvertically aligned leg angles with the angles of each stringhorizontally aligned with those of the other string, and an intermediatestring of vertically aligned leg angles disposed in break-jointrelationship with the inner leg angles, the three strings of leg anglesbeing arranged in back-to-back relationship to form a corner leg columnsubstantially cross-shape in cross section; compound gusset bracketsreversely arranged in pairs and positioned at the abutting ends of theinner leg angles, each bracket having two vertical gusset plate portionsjoined together and two overlapping horizontal gusset plate portionseach extending inwardly from one of said vertical gusset plateportio-ns, each vertical gusset plate being secured to the adjacentinner leg angle and the horizontal gusset plates forming a horizontalgusset plates of each pair of brackets together to connect the several'`leg angles of both inner strings; transverse girts and braces formingvadjacent sides ofthe structure, the girts and braces of each side beingsecured to the adjacent inner legangles and the adjacent brackets; andseparate means for securing the intermediate legv angles to the innerleg angles independently of the girts, braces and brackets.

l2. A combination asdened in claim l1 in which each girt is ofl angle'form and is nested ina horizontal corner of one1of said gusset bracketswith its horizontal flange connected to the horizontal gusset plates ofsaid bracketand its vertical flange connected to the adjacent verticalgusset plate of said bracket.

13. A combination as del-ined in claim l in which the girts of each sidecomprise upper girts secured to the upper ends of the inner leg anglesof the'associated corner leg columns and lower girts secured to thelower ends of said inner leg angles.

In testimony whereof, I have hereunto set my hand at Los Angeles,California, this direct connection between the two innerY strings of legangles; means securing the-

